The present invention relates to a cartridge follower for a tubular magazine for a firearm, and in particular to such a follower that can be identified easily by touch.
Repeating shotguns use tubular linear magazines in which cartridges, also called shells, are stacked one behind another in the magazine. A spring loaded follower at the front end of the magazine pushes back against the front of the first cartridge loaded into the magazine, which will be the last cartridge actually loaded into the chamber of the shotgun. The follower urges the cartridges rearwardly into position to be fed one by one into the chamber. In the past followers have usually had a flat face that contacts the front of a cartridge.
Without operating the loading mechanism, the only way to tell reliably when the magazine of a typical repeating shotgun is empty is to examine the firearm visually. However, this is often impractical. Police and military shotguns are often used under adverse conditions such as at night or when visibility is poor, when it would be dangerous or impossible to visually examine the shotgun.
Many shotguns employ a lifter which elevates each cartridge into alignment for being pushed into the chamber. Between rounds or while the shotgun is being loaded, a finger can be inserted past the lifter to the rear of the magazine, and the next cartridge in the magazine to be loaded, or the follower, can be touched. If the follower and the primer of a cartridge could be distinguished by touch, a user could determine whether a shotgun magazine was empty or not. Because police and military shotguns are often used at night or when visibility is low, a follower that can be distinguished from a shell by touch would be particularly useful to indicate whether the firearm magazine is loaded.
Therefore, several attempts have been made in the past to provide a follower which can be distinguished definitely from a shell by touch. Such a follower should be distinguishable by touch even when the user is wearing gloves, because police and military firearm users frequently wear fire-resistant gloves.
One such previously-known follower 10 has a small raised bump 12 in the center of the face of the follower as shown in FIG. 1. The bump 12 allows a user to distinguish the follower 10 from a cartridge by touch to determine whether the magazine is empty. However, such a centrally located bump 12 has a significant disadvantage. If a shotgun shell were placed backward in the magazine by mistake the bump 12 of the follower would press on the percussion-operated primer located in the center of the base of the shotgun shell, resulting in the risk that the follower could fire the shell in the magazine, causing significant damage and risk of serious injury.
Another prior art follower 14, shown in FIG. 2, has a protruding small end 16 of a central rod surrounded by a deep annular cavity 18. However, it has been found that when a shotgun is employed in field conditions the annular cavity 18 can fill with foreign material and make the end 16 difficult to distinguish from a cartridge by touch. This follower 14 also has the disadvantage of being capable of firing a misloaded shell in the magazine because of the protrusion of the end 16 of its centrally located rod.
Another prior art follower 20, shown in FIG. 3, includes a flat circular protrusion centrally located on the face of the follower 22. The circular protrusion has a diameter of 9.53 mm, and protrudes from the face of the follower 0.89 mm. While such a protrusion is unlikely to set off the primer of a cartridge loaded backwards into the magazine, it is also too broad to be easily distinguishable from a cartridge by touch.
Therefore, what is still needed for a shotgun magazine is a cartridge follower that can be distinguished easily from a shell by touch, but which cannot easily fill with foreign material or accidentally discharge a shell inadvertently loaded backwards into the magazine.
The present invention overcomes the drawbacks of the prior art by providing for use in a shotgun magazine a follower that can be distinguished from a shell by touch but which cannot inadvertently discharge a shell loaded backwards in the magazine. The invention provides a follower for pushing against cartridges with a front face that has at least one protruding member offset from the center of the face. The follower thus is easily identifiable by touch, but cannot fire a shell inadvertently loaded backwards into the magazine.
In one preferred embodiment of the invention the follower has at least two protruding members each located far enough from the center of the front face to avoid contact with the primer of a shell loaded backward in the magazine.
The present invention also provides a method for determining whether a shotgun magazine is empty by providing, in the magazine, a cartridge follower with a front face for pushing against cartridges which has at least one protruding member offset from the center of the front face, and determining whether the magazine is empty by inserting a finger into the outfeed end of the magazine and attempting to feel the protruding member of the follower.
The invention thus allows the user of a shotgun to distinguish by feel between the follower of the magazine cartridge and a shell remaining in the magazine, thereby determining whether or not he or she needs to reload and whether the firearm is safe to be transported. This determination can be made at night or under conditions of low visibility such as are often encountered by police and military shotgun users. The determination can be made regardless of whether the breech of the shotgun is open or closed, making the invention particularly valuable for police or military users who may be endangered unnecessarily if they run out of ammunition or mishandle a loaded firearm believed to be empty.
The foregoing and other objectives, features, and advantages of the invention will be more readily understood upon consideration of the following detailed description of the invention, taken in conjunction with the accompanying drawings.